Display panel

ABSTRACT

A display panel is disclosed, which includes: a first substrate; a first metal line disposed above the first substrate and having a first surface and a first side, wherein the first side connects to the first surface, and the first side has a concave shape; and a sealant unit in contact with the first metal line, wherein the first metal line includes a first metal layer, a second metal layer and a third metal layer, the second metal layer locates between the first metal layer and the third metal layer, the sealant covers at least a portion of the first metal layer, and a part of the sealant locates between the first metal layer and the third metal layer.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefits of the Taiwan Patent ApplicationSerial Number 104110662, filed on Apr. 1, 2015, the subject matter ofwhich is incorporated herein by reference.

This application is a continuation (CA) of U.S. Patent application for“DISPLAY PANEL”, U.S. application Ser. No. 14/808,300 filed Jul. 24,2015, and the subject matter of which is incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The disclosure relates to a display panel and, more particularly, to adisplay panel having metal layers have specific structures.

2. Description of Related Art

In recent years, all the display devices are developed toward havingsmall volume, thin thickness and light weight as the display techniquesprogresses. Hence, a conventional cathode ray tube (CRT) display isgradually replaced by flat panel display devices such as a liquidcrystal display (LCD) device and an organic light emitting diode (OLED)display device. The flat panel display devices can be applied to variousfields. For example, the daily used devices such as cell phones,notebooks, video cameras, cameras, music players, navigation devices,and televisions are equipped with the flat panel display devices.

Although the LCD device and the OLED display device are commerciallyavailable and especially the techniques for the LCD device are muchmature, every manufacturer is desired to develop display devices withimproved display quality to meet customers' requirement as the displaydevices developed. In particular, the structure of the TFT substrate isone factor related to the display quality.

Even though the LCD device and the OLED display device are welldeveloped and commercialized, it is still necessary to develop a displaydevice with improved display quality to meet the customers' requirement.

SUMMARY OF THE INVENTION

The object of the disclosure is to provide a display panel, wherein ametal line in a non-display region is designed to have a specificstructure to increase the adhesion of a sealant to the metal line, and ametal line in a display region is also designed to have a specificstructure to decrease the resistance of the metal line in the displayregion.

One aspect of the disclosure is to provide a display panel, whichcomprises: a first substrate; a first metal line disposed on the firstsubstrate and having a first surface and a first side connecting to thefirst surface, wherein the first side has a concave shape; and a sealantcovering the first surface and the first side.

In the display panel of this aspect, the first metal line comprises afirst metal layer and a second metal layer, the second metal layerlocates between the first metal layer and the first substrate, and thesealant covers the first metal layer.

In the display panel of this aspect, the first side of the second metallayer is relatively away from a substrate edge of the first substrate,compared with the first side of the first metal layer.

In the display panel of this aspect, the first metal line furthercomprises a third metal layer, the second metal layer locates betweenthe first metal layer and the third metal layer, and the sealant furtherlocates between the first metal layer and the third metal layer.

In the display panel of this aspect, the first side of the second metallayer is relatively away from a substrate edge of the first substrate,compared with the first side of the first metal layer and the thirdmetal layer.

In the display panel of this aspect, an acute angle is included betweenthe first surface and the first side.

In the display panel of this aspect, the first metal line further has asecond surface opposite to the first surface and connecting to the firstside, and an acute angle is included between the second surface and thefirst side.

In the display panel of this aspect, the sealant is a frit sealant.

In the display panel of this aspect, the first substrate has a displayregion and a non-display region surrounding the display region, thefirst metal line is disposed on the non-display region, and the displaypanel further comprises: an insulating layer disposed on the firstsubstrate and having a contact via locating in the display region; and asecond metal line disposed in the contact via and having a thirdsurface, wherein the third surface has a central region and a borderregion, the border region is relatively near to a side wall of thecontact via compared with the central region, and the central region ismore protruded than the border region.

Another aspect of the disclosure is to provide another display panel,which comprises: a first substrate having a display region; aninsulating layer disposed on the first substrate and having a contactvia locating in the display region; and a second metal line disposed inthe contact via and having a third surface, wherein the third surfacehas a central region and a border region, the border region isrelatively near to a side wall of the contact via compared with thecentral region, and the central region is more protruded than the borderregion.

In the display panel of this aspect, the second metal line comprises afourth metal layer and a fifth metal layer, the fifth metal layerlocates between the first substrate and the fourth metal layer, and thefourth metal layer has a third surface and a second side, in which thethird surface connects to the second side and an obtuse angle isincluded between the third surface and the second side.

The display panel of this aspect may further comprise an organic displaymedium disposed on the second metal line.

In the display panel of this aspect, a thickness of the central regionof the second metal line is larger than that of the border regionthereof.

In the display panel of this aspect, the first substrate furthercomprises a non-display region surrounding the display region, and thedisplay panel further comprises: a first metal line disposed in thenon-display region and having a first surface and a first sideconnecting to the first surface, wherein the first side has a concaveshape; and a sealant covering the first surface and the first side.

In the display panel of this aspect, the sealant is a frit sealant.

In the display panel of this aspect, the first metal line comprises afirst metal layer and a second metal layer, the second metal layerlocates between the first metal layer and the first substrate, and thesealant convers the first metal layer.

In the display panel of this aspect, the first metal line furthercomprises a third metal layer, the second metal layer locates betweenthe first metal layer and the third metal layer, and the sealant furtherlocates between the first metal layer and the third metal layer.

In the display panel of this aspect, the first side of the second metallayer is relatively away from a substrate edge of the first substrate,compared with the first side of the first metal layer and the thirdmetal layer.

In the display panel of this aspect, an acute angle is included betweenthe first surface and the first side.

In the display panel of this aspect, the first metal line further has asecond surface opposite to the first surface and connecting to the firstside, and an acute angle is included between the second surface and thefirst side.

In the display panels provided by the aforementioned aspects of thedisclosure, the metal line in the non-display region is designed to havea specific structure, and especially the side of the metal line in thenon-display region is designed to have a concave shape. Hence, theadhesion of the sealant to the metal line can be increased during theprocess for coating the sealant, further preventing the peeling of thesealant. Meanwhile, the metal line in the display region is alsodesigned to have a specific structure, and especially the central regionof the metal line in the contact via is designed to be more protrudedthan the border region. Hence, a cross-sectional area of the metal linecan be increased, further decreasing the resistance of the metal lineduring the operation of the display panel. Herein, the shape of themetal line in the display region does not have the concave shape as thatin the non-display region. Charges may be accumulated at the sharpcorner corresponding to the acute angle included between the surface andthe side of the metal line in the non-display region and the accumulatedcharges may cause the point discharge occurred. However, an obtuse angleis included between the surface and the side of the metal line in thedisplay region, and the metal line therein has a relatively smoothinclined shape. Hence, there is no sharp corner formed in the displayregion, and thus the point discharge and the problem of the decreasedanti-static capability in the display region can be prevented.

Other objects, advantages, and novel features of the invention willbecome more apparent from the following detailed description when takenin conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of an OLED display panel according toone preferred embodiment of the disclosure;

FIG. 2 is a schematic view showing a layout of an OLED display panelaccording to one preferred embodiment of the disclosure;

FIG. 3 is a cross-sectional view of a thin film transistor (TFT)substrate of an OLED display panel according to one preferred embodimentof the disclosure;

FIG. 4A is a cross-sectional view showing parts of a display region anda non-display region of an OLED display panel according to one preferredembodiment of the disclosure; and

FIG. 4B is a cross-sectional view showing parts of a display region anda non-display region of an OLED display panel according to anotherpreferred embodiment of the disclosure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The disclosure has been described in an illustrative manner, and it isto be understood that the terminology used is intended to be in thenature of description rather than of limitation. Many modifications andvariations of the disclosure are possible in light of the aboveteachings. Therefore, it is to be understood that within the scope ofthe appended claims, the invention may be practiced otherwise than asspecifically described.

FIG. 1 is a cross-sectional view of an OLED display panel according toone preferred embodiment of the disclosure. During the process formanufacturing the OLED display panel, a first substrate 11 and a secondsubstrate 12 are firstly provided. Organic light emitting diode (OLED)units 15 and pixel defining layers 16 are disposed on the firstsubstrate 11, wherein each pixel defining layer 16 is disposed betweentwo adjacent OLED units 15. In addition, plural spacers 14 are disposedon the second substrate 12, and a sealant 13 (a frit sealant in thepresent embodiment) is formed on a periphery of the second substrate 12in advance, which is formed through a dispensing process and a sinteringprocess to be fixed on the second substrate 12. Then, the firstsubstrate 11 is assembled with the second substrate 12, wherein thespacers 14 on the second substrate 12 correspond to regions outside thepixel opening 161 of the pixel defining layer 16. After the sealant 13is adhered onto the first substrate 11 through a laser process, an OLEDdisplay panel of the present embodiment is obtained.

In the present embodiment, both the first substrate 11 and the secondsubstrate 12 are glass substrates. In addition, the OLED display deviceof the present embodiment comprises a display region A and a non-displayregion B, wherein the non-display region B is a region with circuitsformed thereon, and the display region A is a region with theaforementioned OLED units 15 and TFT units (not shown in the figure)formed thereon. Furthermore, in the present embodiment, the OLED units15 can respectively emit red, green and blue light; but the disclosureis not limited thereto. For example, the OLED units 15 can be white OLEDunits, and a color filter unit (not shown in the figure) is furtherdisposed on a side of the first substrate 11 or the second substrate 12.

In addition, in the OLED display panel of the present embodiment, theOLED units 15 comprise a first electrode 151, an organic display medium152 and a second electrode 153 sequentially laminated on the firstsubstrate 11. Herein, the first electrode 151 electrically connects tothe TFT units (not shown in the figure) on the first substrate 11. Thepixel defining layer 16 is disposed between the first electrode 151 andthe organic display medium 152, and a light emitting region is definedby the pixel opening 161 of the pixel defining layer 16.

Furthermore, in the OLED display panel of the present embodiment, thefirst electrode 151 can be made of any material for reflectiveelectrodes or transparent electrodes generally used in the art, and thesecond electrode 153 can be made of any material for transparent orsemi-transparent electrodes generally used in the art. The materials forthe reflective electrodes may be Ag, Ge, Al, Cu, Mo, Ti, Sn, AlNd, ACXor APC, the materials for the transparent electrodes may be transparentconductive oxides (TCO) such as ITO and IZO, and the semi-transparentelectrodes may be metal thin film electrodes such as Mg/Ag alloy thinfilm electrodes, Au thin film electrodes, Pt thin film electrodes and Althin film electrodes. In addition, the second electrode 153 used hereincan be a composite electrode of a transparent electrode and asemi-transparent electrode (for example, a composite electrode of a TCOelectrode and a Pt thin film electrode), if it is needed. Herein, onlythe OLED unit comprising the first electrode 151, the organic displaymedium 152 and the second electrode 153 is present, but the disclosureis not limited thereto. Other OLED units generally used in the art canalso be applied to the OLED display panel of the disclosure, forexample, the OLED unit comprising an electron transporting layer, anelectron injection layer, a hole transporting layer, a hole injectionlayer, and/or other layers capable of facilitating the combination ofholes and electrons.

FIG. 2 is a schematic view showing a layout of an OLED display device ofthe present embodiment. As shown in FIG. 2, in the OLED display panel ofthe present embodiment, each pixel unit respectively comprises: a scanline, a data line, a capacitor line, a supply line, a switching TFT unit(shown as switching TFT in FIG. 2), a driving TFT unit (shown as drivingTFT in FIG. 2), a storage capacitor, and an OLED unit (shown as OLED inFIG. 2) connecting to a first electrode and a second electrode.

FIG. 3 is a cross-sectional view showing a TFT substrate of the OLEDdisplay panel of the present embodiment. As shown in FIGS. 1 and 3, theTFT substrate of the present embodiment comprises: a first substrate;and TFT unis disposed thereon. As shown in FIG. 3, in the display regionA shown in FIG. 1, a first substrate 11 is firstly provided, and anactive layer 101 is further formed thereon. In the present embodiment,the active layer 101 is made of polysilicon formed by annealingamorphous silicon. Then, a first insulating layer 102, a bottom metallayer 103 and a second insulating layer 104 are sequentially formed onthe first substrate 11. Herein, the bottom metal layer 103 located inthe TFT regions TFT1, TFT2 is served as gate electrodes. The firstinsulating layer 102 is served as a gate insulating layer, which is madeof any insulating material generally used in the art, such as siliconoxides and silicon nitrides. In addition, the second insulating layer104 can also be made by the aforementioned insulating material generallyused in the art. Next, an upper metal layer 105 is formed on the secondinsulating layer 104. Herein, the upper metal layer 105 located in theTFT regions TFT1, TFT2 further penetrate through the first insulatinglayer 102 and the second insulating layer 104, to be used as a sourceelectrode and a drain electrode electrically connecting to the activelayer 101. After the aforementioned process, the TFT substrate of thepresent embodiment is obtained.

In the present embodiment, the TFT substrate comprises two TFT regionsTFT1, TFT2, wherein the TFT region TFT1 corresponds to the switching TFTshown in FIG. 2, and the TFT region TFT2 corresponds to the driving TFTshown in FIG. 2. In addition, in the present embodiment, except for theTFT regions TFT1, TFT2, a capacitor region C is also formed, whichcorresponds to the storage capacitor shown in FIG. 2. In the presentembodiment, the TFT unit on the TFT substrate is a low temperaturepoly-silicon (LTPS) TFT unit. However, in other embodiment of thedisclosure, the structure of the TFT unit is not limited to that shownin FIG. 3. In addition, in other embodiment of the disclosure, the TFTunit does not only comprise the layers shown in FIG. 3, and may alsocomprise other layers such as buffer layers and other insulating layers,to increase the adhesion between layers and the electricity of the TFTunit.

In the present embodiment, the upper metal layer may be formed by anyprocess known in the art, such as deposition and electroplating. Herein,in order to increase the adhesion of the upper metal layer in thenon-display region and decrease the resistance of the upper metal layerin the display region, a patterning process by using a mask (forexample, an etching by using a mask) may be performed on the upper metallayer to make the upper metal layer have a predetermined pattern.Alternatively, a printing process may be performed to directly form anupper metal layer having a predetermined pattern.

Hereinafter, the structure of the upper metal layer in the displayregion and the non-display region of the OLED display panel of thepresent embodiment is illustrated in detail.

As shown in FIG. 4A, which is a cross-sectional view showing parts ofthe display region and the non-display region of the OLED display panelof the present embodiment, wherein the left side of FIG. 4A shows across-section of partial non-display region B in FIG. 1, and the rightside thereof shows a cross-section of partial display region A in FIG. 1and especially the region E in FIG. 3.

As shown in FIG. 4A, in the non-display region of the OLED display panelof the present embodiment, the display panel comprises: a firstsubstrate 11 with a substrate edge 111; a first metal line 115 disposedon the first substrate 11, wherein the first metal line 115 is one metalline comprised in the aforementioned formed upper metal layer, the firstmetal line 115 has a first surface 1151, a second surface 1153 oppositeto the first surface 1151, and a first side 1152 locating between thefirst surface 1151 and the second surface 1153 and connecting to thefirst surface 1151 and the second surface 1153; and a sealant 13covering the first surface 1151 and the first side 1152. Morespecifically, the sealant 13 covers partial first surface 1151 and thewhole first side 1152.

In the present embodiment, the first side 1152 of the first metal line115 has a concave shape. More specifically, the first metal line 115comprises a first metal layer 115 a, a second metal layer 115 b and athird metal layer 115 c, the second metal layer 115 b locates betweenthe first metal layer 115 a and the first substrate 11 and also betweenthe first metal layer 115 a and the third metal layer 115 c. In thiscase, the sealant 13 covers the first metal layer 115 a, and furtherlocates between the first metal layer 115 a and the third metal layer115 c. In other words, the first side 1152 of the second metal layer 115b is relatively away from the substrate edge 111 of the first substrate11, compared with the first side 1152 of the first metal layer 115 a andthe third metal layer 115 c. That is, a distance D2 between any end ofthe first side 1152 of the second metal layer 115 b and an extensionline of the substrate edge 111 is larger than minimum distances D1, D3between any ends of the first side 1152 of the first metal layer 115 aand the third metal layer 115 c and the extension line of the substrateedge 111. In addition, an acute angle θ1 is included between the firstsurface 1151 and the first side 1152, and another acute angle θ2 isincluded between the second surface 1153 and the first side 1152. In thepresent embodiment, the acute angles θ1, θ2 are not particularlylimited, as long as in a range between 0 degree and 90 degree.Furthermore, the first side 1152 of the first metal line 115 has notonly the concave shape but also a rough surface.

In the OLED display panel of the present embodiment, the first side 1152of the first metal line 115 is designed to have a concave shape, so theadhesion between the first metal line 115 and the sealant 13 can beincreased to prevent the peeling of the sealant 13 during the processfor coating the sealant 13; therefore, the yield rate of the displaypanel can be improved. Furthermore, the first side 1152 of the firstmetal line 115 is also designed to have a rough surface, to furtherimprove the adhesion between the first metal line 115 and the sealant13.

However, if the metal line in the display region is designed to have theconcave shape as that in the non-display region, charges may be easilyaccumulated at the sharp corner near to the surface of the metal linesand the anti-static capability of the display region will be decreased.Hence, in the OLED display panel of the disclosure, the shapes of themetal lines in the display region and the non-display region aredifferent.

As shown in FIGS. 3 and 4A, in the display region of the OLED displaypanel of the present embodiment, the display panel comprises: a firstsubstrate 11; an insulating layer (comprising the first insulating layer102 and the second insulating layer 104) disposed on the first substrate11 and having a contact via 1121; and a second metal line 116 disposedin the contact via 1121, wherein the second metal line 116 is one metalline comprised in the aforementioned formed upper metal layer, thesecond metal line 116 has a third surface 1161 and a second side 1162connecting to the third surface 1161, the third surface 1161 has acentral region C and a border region P, the border region P isrelatively near to a side wall of the contact via 1121 compared with thecentral region C, and the central region C is more protruded than theborder region P. More specifically, a thickness of the central region Cof the second metal line 116 is larger than that of the border region Pthereof. When the central region C of the second metal line 116 isdesigned to be more protruded than the border region P thereof, asectional area of the second metal line 116 can be increased; thus, theresistance of the second metal line 116 can be decreased to improve theelectricity of the TFT units (not shown in the figure).

In addition, in the display region of the OLED display panel of thepresent embodiment, the second metal line 116 comprises a fourth metallayer 116 a, a fifth metal layer 116 b, and a sixth metal layer 116 c,wherein the fifth metal layer 116 b locates between the first substrate11 and the fourth metal layer 116 a and between the fourth metal layer116 a and the sixth metal layer 116 c. Herein, the fourth metal layer116 a has a third surface 1161 and a second side 1162, in which thethird surface 1161 connects to the second side 1162 and an obtuse angleθ3 is included between the third surface 1161 and the second side 1162.In the present embodiment, the degree of the obtuse angle θ3 is notparticularly limited, as long as in a range between 90 degree and 180degree.

Please compare the display region shown in the left side of FIG. 4A withthe non-display region shown in the right side thereof. It can be foundthat the first side 1152 of the first metal line 115 has a concave shapeand a rough surface, but the second side 1162 of the second metal line116 has a relatively smooth inclined shape. More particularly, the acuteangles θ1, θ2 are respectively included between the first side 1152 andthe first surface 1151 as well as the second surface 1153 of the firstmetal line 115 in the non-display region, but an obtuse angle θ3 isincluded between the third surface 1161 and the second side 1162 of thesecond metal line 116 in the display region. Hence, in the display panelof the present embodiment, no sharp corner (as that present in the firstmetal line 115 in the non-display region) is present in the second metalline 116 in the display region, so the problem of charge accumulationcan be prevented and the anti-static capability of the units in thedisplay region can further be improved.

FIG. 4B is a cross-sectional view showing parts of the display regionand the non-display region of the OLED display panel of anotherembodiment in the disclosure. Herein, the structure and themanufacturing process of the OLED display panel of the presentembodiment are the same as those illustrate in the aforementionedembodiment, except that the first metal line 115 in the presentembodiment does not comprise the third metal layer 115 c, and the secondmetal line 116 does not comprise the sixth metal layer 116 c. Hence, inthe present case, the first metal line 115 only comprise the first metallayer 115 a and the second metal layer 115 b, wherein the second metallayer 115 b locates between the first metal layer 115 a and the firstsubstrate 11, and the sealant 13 covers the first metal layer 115 a.Meanwhile, the first side 1152 of the second metal layer 115 b isrelatively away from the substrate edge 111 of the first substrate 11,compared with the first side 1152 of the first metal layer 115 a.

In the present embodiment, as shown in FIGS. 3, 4A and 4B, the materialsfor the bottom metal layer 103 and the upper metal layer 105 for formingthe first metal line 115 and the second metal line 116 are notparticularly limited, and can be any material for metal electrodesgenerally used in the art. In the aforementioned embodiment of thedisclosure, the material for the bottom metal layer 103 is Mo, that forthe first metal layer 115 a is Ti, that for the second metal layer 115 bis Al, that for the third metal layer 115 c is Ti, that for the fourthmetal layer 116 a is Ti, that for the fifth metal layer 116 b is Al, andthat for the sixth metal layer 116 c is Ti.

In the OLED display panels provided by the aforementioned embodiments ofthe disclosure, the first metal line and the second metal line can bethe same conductive line or different conductive lines, and notparticularly limited, as long as the first metal line and the secondmetal line have the aforementioned features.

In the present embodiments, OLED display panels are provided. However,in other embodiment of the disclosure, the aforementioned TFT substratecan also be applied on a LCD panel. When the aforementioned TFTsubstrate is applied on a LCD panel, the obtained LCD panel is furtherassembled with a backlight module to obtain a LCD device.

The display panel provided by the aforementioned embodiment can beco-used with any touch panel known in the art, to obtain a touch displaydevice.

In addition, the display device provided by the disclosure can beapplied to any electronic device for displaying images, such as a mobilephone, a notebook, a camera, a video camera, a music player, anavigation system, or a television.

Although the disclosure has been explained in relation to its preferredembodiment, it is to be understood that many other possiblemodifications and variations can be made without departing from thespirit and scope of the invention as hereinafter claimed.

What is claimed is:
 1. A display panel, comprising: a first substrate; afirst metal line disposed above the first substrate and having a firstsurface and a first side, wherein the first side connects to the firstsurface, and the first side has a concave shape; and a sealant incontact with the first metal line, wherein the first metal linecomprises a first metal layer, a second metal layer and a third metallayer, the second metal layer locates between the first metal layer andthe third metal layer, the sealant covers at least a portion of thefirst metal layer, and a part of the sealant locates between the firstmetal layer and the third metal layer.
 2. The display panel as claimedin claim 1, wherein the second metal layer locates between the firstmetal layer and the first substrate.
 3. The display panel as claimed inclaim 2, wherein a first part of the first side corresponding to thefirst metal layer is closer to a substrate edge of the first substratethan a second part of the first side corresponding to the second metallayer.
 4. The display panel as claimed in claim 3, wherein a third partof the first side corresponding to the third metal layer is closer tothe substrate edge of the first substrate than the second part of thefirst side corresponding to the second metal layer.
 5. The display panelas claimed in claim 1, wherein an acute angle is included between thefirst surface and the first side.
 6. The display panel as claimed inclaim 1, wherein the first metal line further has a second surfaceopposite to the first surface and connecting to the first side, and anacute angle is included between the second surface and the first side.7. The display panel as claimed in claim 1, wherein the sealant is afrit sealant.
 8. The display panel as claimed in claim 1, wherein thefirst substrate has a display region and a non-display region adjacentto the display region, the first metal line is disposed above thenon-display region, the first substrate further has a top surface, andthe display panel further comprises: an insulating layer disposed abovethe top surface of the first substrate, wherein the insulating layer hasa contact via locating in the display region; and a second metal linecovering at least a portion of the insulating layer, wherein a firstportion of the second metal line is disposed in the contact via, whereinthe second metal line comprises a fourth metal layer and a fifth metallayer, the fifth metal layer locates between the first substrate and thefourth metal layer, the fourth metal layer further has a second side, asurface of the fourth metal layer connects to the second side, and anobtuse angle is included between the surface of the fourth metal layerand the second side.
 9. A display panel, comprising; a first substratehaving a display region and a top surface; an insulating layer disposedabove the top surface of the first substrate, wherein the insulatinglayer has a contact via locating in the display region; a second metalline covering at least a portion of the insulating layer, wherein afirst portion of the second metal line is disposed in the contact via,and the first portion of the second metal line has a third surface; anda display medium disposed above the second metal line, wherein the thirdsurface has a central region and a border region, the border region isrelatively near to a side wall of the contact via compared with thecentral region, a distance between the top surface and the centralregion of the third surface is a first thickness, a distance between thetop surface and the border region of the third surface is a secondthickness, and the first thickness is greater than the second thickness.10. The display panel as claimed in claim 9, wherein the second metalline comprises a fourth metal layer and a fifth metal layer, the fifthmetal layer locates between the first substrate and the fourth metallayer, the fourth metal layer further has a second side, a surface ofthe fourth metal layer connects to the second side, and an obtuse angleis included between the surface of the fourth metal layer and the secondside.
 11. The display panel as claimed in claim 9, wherein the displaymedium is an organic display medium.
 12. The display panel as claimed inclaim 9, wherein the first substrate further comprises a non-displayregion adjacent to the display region, and the display panel furthercomprises: a first metal line disposed in the non-display region andhaving a first surface and a first side, wherein the first side connectsto the first surface, and the first side has a concave shape; and asealant in contact with the first surface and the first side.
 13. Thedisplay panel as claimed in claim 12, wherein the sealant is a fritsealant.
 14. The display panel as claimed in claim 12, wherein the firstmetal line comprises a first metal layer and a second metal layer, thesecond metal layer locates between the first metal layer and the firstsubstrate, and the sealant covers at least a portion of the first metallayer.
 15. The display panel as claimed in claim 14, wherein the firstmetal line further comprises a third metal layer, the second metal layerlocates between the first metal layer and the third metal layer, and apart of the sealant further locates between the first metal layer andthe third metal layer.
 16. The display panel as claimed in claim 15,wherein a first part of the first side corresponding to the first metallayer is closer to a substrate edge of the first substrate than a secondpart of the first side corresponding to the second metal layer, and athird part of the first side corresponding to the third metal layer iscloser to the substrate edge of the first substrate than the second partof the first side corresponding to the second metal layer.
 17. Thedisplay panel as claimed in claim 12, wherein an acute angle is includedbetween the first surface and the first side.
 18. The display panel asclaimed in claim 12, wherein the first metal line further has a secondsurface opposite to the first surface and connecting to the first side,and an acute angle is included between the second surface and the firstside.